Abstract：
Total ankle arthroplasty is the gold standard surgical treatment for severe ankle arthritis and fracture. However, revision surgeries due to the in vivo failure of the ankle implant are a serious concern. Extreme bone density loss due to bone remodelling is one of the main reasons for in situ implant loosening, with aseptic loosening of the talar component being one of the primary reasons for total ankle arthroplasty revisions. This study is aimed at determining the performance and potential causes of failure of the talar component. Herein, we investigated the stress, strain, and bone density changes that take place in the talus bone during the first 6 months of bone remodelling due to the total ankle arthroplasty procedure. Computed tomography scans were used to generate the 3D geometry used in the finite element (FE) model of the Intact and implanted ankle. The Scandinavian Total Ankle Replacement (STAR™) CAD files were generated, and virtual placement within bone models was done following surgical guidelines. The dorsiflexion physiological loading condition was investigated. The cortical region of the talus bone was found to demonstrate the highest values of stress (5.02 MPa). Next, the adaptive bone remodelling theory was used to predict bone density changes over the initial 6-month post-surgery. A significant change in bone density was observed in the talus bone due to bone remodelling. The observed quantitative changes in talus bone density over 6-month period underscore potential implications for implant stability and fracture susceptibility. These findings emphasise the importance of considering such biomechanical factors in ankle implant design and clinical management.
摘要：
全踝关节置换术是治疗严重踝关节关节炎和骨折的金标准。然而,由于踝关节植入物的体内失败而进行的翻修手术是一个严重的问题。骨重建导致的极度骨密度丢失是原位种植体松动的主要原因之一,距骨部分的无菌性松动是全踝关节置换术的主要原因之一。这项研究旨在确定距骨组件的性能和潜在故障原因。在这里，我们调查了压力，应变，和骨密度的变化，发生在头6个月的骨重塑过程中，由于全踝关节置换术。使用计算机断层扫描来生成完整和植入踝关节的有限元（FE）模型中使用的3D几何形状。生成了斯堪的纳维亚全踝关节置换术（STAR™）CAD文件，骨模型内的虚拟放置按照手术指南进行.研究了背屈生理负荷条件。发现距骨的皮质区域显示出最高的应力值（5.02MPa）。接下来,自适应骨重建理论用于预测术后最初6个月的骨密度变化.由于骨重塑，在距骨中观察到骨密度的显着变化。在6个月内观察到的距骨骨密度的定量变化强调了对植入物稳定性和骨折敏感性的潜在影响。这些发现强调了在踝关节植入物设计和临床管理中考虑这些生物力学因素的重要性。
